The present invention relates generally to a method of selective fluorination of actinide species, and more particularly to the removal of plutonium impurity from americium using fluorine gas followed by O.sub.2 F.
Americium is a by product of plutonium production, and is currently extracted from solutions of plutonium feedstock material by a peroxide precipitation process. However, the americium recovered by this process contains between approximately 1 and 20% of plutonium. Excess peroxide is subsequently neutralized by addition of caustic, forming thereby polyhydroxides of americium. Further purification is required to reduce the plutonium impurity to an acceptable 5000 ppm level. This is accomplished by dissolving the impure americium hydroxides in nitric acid an passing the resulting solution through ion-exchange material wherein the plutonium is preferentially fixed while the americium remains in solution, thereby passing through the exchange material. To produce metallic americium, the processed americium solution is mixed with oxalic acid to precipitate the americium as americium oxalate which is then calcined at about 450.degree. C. to yield AmO.sub.2. The oxide material may then be reduced to the metal. Of interest is a less complicated procedure for further reducing the plutonium content of americium.
Accordingly, it is an object of the present invention to provide a method for the reduction of the plutonium impurity content of americium.
Another object of the invention is to provide a nonaqueous procedure for reducing the plutonium impurity in americium.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.